package zuoye01;

public class Circle {
private static  final double pai=3.14;
public double area(double radius){
    return pai*radius*radius;

}

    public static void main(String[] args) {
        Circle circle=new Circle();
        double radius=10;
        double area=circle.area(radius);
        System.out.println("这个圆的半径是"+radius+"面积是"+area) ;
    }
}